Feature/thesis work merge (#566)

Web GUI from Klas Eskilson (three new modules: webgui, webbrowser and cefwebgui)
Parallel connection refactorization
Wormhole server added to the main repository
Transfer function editor work from Cristoffer Särevall
Update ghoul

modules/volume/transferfunctionhandler.h

@@ -0,0 +1,86 @@
+/*****************************************************************************************
+*                                                                                       *
+* OpenSpace                                                                             *
+*                                                                                       *
+* Copyright (c) 2014-2017                                                               *
+*                                                                                       *
+* Permission is hereby granted, free of charge, to any person obtaining a copy of this  *
+* software and associated documentation files (the "Software"), to deal in the Software *
+* without restriction, including without limitation the rights to use, copy, modify,    *
+* merge, publish, distribute, sublicense, and/or sell copies of the Software, and to    *
+* permit persons to whom the Software is furnished to do so, subject to the following   *
+* conditions:                                                                           *
+*                                                                                       *
+* The above copyright notice and this permission notice shall be included in all copies *
+* or substantial portions of the Software.                                              *
+*                                                                                       *
+* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,   *
+* INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A         *
+* PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT    *
+* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF  *
+* CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE  *
+* OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                                         *
+****************************************************************************************/
+
+#ifndef __OPENSPACE_MODULE_VOLUME___TRANSFERFUNCTIONHANDLER___H__
+#define __OPENSPACE_MODULE_VOLUME___TRANSFERFUNCTIONHANDLER___H__
+
+#include <functional>
+#include <ghoul/opengl/texture.h>
+#include <ghoul/glm.h>
+#include <openspace/properties/propertyowner.h>
+#include <openspace/properties/triggerproperty.h>
+#include <openspace/properties/stringproperty.h>
+#include <openspace/properties/binaryproperty.h>
+#include <openspace/properties/scalarproperty.h>
+#include <openspace/util/histogram.h>
+#include <modules/volume/transferfunctionproperty.h>
+#include <modules/volume/transferfunction.h>
+#include <openspace/rendering/transferfunction.h>
+
+#include <vector>
+#include <memory>
+
+namespace openspace {
+namespace volume {
+
+class Envelope;
+        
+class TransferFunctionHandler : public properties::PropertyOwner{
+public:
+    TransferFunctionHandler(const properties::StringProperty& prop);
+            
+    void initialize();
+            
+    void setHistogramProperty(std::shared_ptr<openspace::Histogram> histogram);
+
+    void setTexture();
+    void loadStoredEnvelopes();
+    void saveEnvelopes();
+    void setFilepath(const std::string& path);
+    void setUnit(const std::string& unit);
+    void setMinAndMaxValue(const float& min, const float& max);
+
+    ghoul::opengl::Texture& getTexture();
+    void uploadTexture();
+    bool hasTexture();
+
+    std::shared_ptr<openspace::TransferFunction> getTransferFunction();
+
+private:
+    bool useTxtTexture = true;
+    properties::StringProperty _transferFunctionPath;
+    properties::StringProperty _dataUnit;
+    properties::StringProperty _minValue;
+    properties::StringProperty _maxValue;
+    properties::TriggerProperty _saveTransferFunction;
+    std::string _filePath;
+    properties::TransferFunctionProperty _transferFunctionProperty;
+    properties::BinaryProperty _histogramProperty;
+    std::shared_ptr<openspace::TransferFunction> _transferFunction;
+    std::shared_ptr<ghoul::opengl::Texture> _texture = nullptr;
+};
+
+}//namespace volume
+}//namespace openspace
+#endif __OPENSPACE_MODULE_VOLUME___TRANSFERFUNCTIONHANDLER___H__